The invention relates to a production facility for automatically manufacturing parts. In particular, the invention relates to a pallet carousel facility for manufacturing reinforced concrete elements and/or a facility for manufacturing reinforcement elements, having an electronic control computer, which is connected to sensors and control elements of the production facility and which controls the production functional sequence. At least one display device is provided for the schematic graphical representation of the production facility and the current status data thereof.
Production facilities, or pallet carousel facilities, for manufacturing concrete elements are known in principle from, for example, EP 2 119 542 A2, EP 2 017 049 A2 and DE 34 16 028 C2.
In comparison with otherwise conventional production lines, such as, for instance, those known from the automobile industry, most modern prefabricated-part carousels have a characteristic feature that to a large extent influences the entire machine technology: it is not a series of products that are being manufactured, but only single products. Moreover the single products have a very high degree of variability. This presents a particular challenge, both for the machines and for functional sequence organization of the production facility. In particular, procedures or sequences cannot be predefined in a specific manner (so-called “teach-in”) but, instead, everything is calculated just-in-time on the basis of the available online data. The machines forming the production facility thus behave as determined by their algorithms on the basis of the part to be produced, and have not been specially set to the prefabricated part to be produced. Likewise, the people working in the production facility must decide just-in-time how to react to a particular situation and how to prioritize their activities.
In the case of highly automated installations, there is the additional difficulty that there can be several initially independent sub-carousels, which have their own functional sequence but which then have to make their component product available in a timely manner at a transfer point. Thus, for example, the reinforcement facility according to FIG. 1 is initially an autonomous part that has its own timing. However, at the “reinforcement transfer” point, the reinforcement must be transferred to the carousel pallet, in such a way that the latter does not have to wait. In order to decouple the timing of the production of such parts, there is usually a small intermediate buffer, but this has only a limited capacity. If this buffer is completely full or completely empty, one of the sub-systems necessarily has to wait. Furthermore, this sub-system problem in itself is not out of the ordinary, but becomes unusually problematic only by the fact that there is no iterative series production, but instead a product sequence that is continuously changing in a fundamental manner.
The above-mentioned single part production (not series production) makes it difficult to make performance analyses. This is because, on the one hand, the production situation is changing continuously, and in a non-reproducible manner. On the other hand, there is also a high degree of mutual influence between the individual products. One and the same product can pass quickly or slowly through the facility, depending on its “compatibility” with the immediately preceding or succeeding products. (This is primarily a matter of full utilization of machinery and personnel; the conventional production-line tasks, aimed at minimizing tool change-over times, are of somewhat secondary importance here).
There can be multiple causes for the performance of such a production facility running well below expectations, for example:                Individual machines are too slow.        Individual machines have too many malfunctions.        Malfunctions are not eliminated sufficiently quickly by personnel (personnel priorities are unfavourable).        Unfavourable travel paths result in parts of the facility mutually interfering (incorrect functional sequence planning).        The personnel do not succeed in completing certain manual operations in a timely manner.        Required supplementary material (built-in components) is not available in a timely manner.        For whatever reasons, the intermediate buffers do not work as originally planned.        The intermediate buffers are too small.        The combination of differing products on one production unit (production pallet) is unfavourable.        
The above stated causes for poor performance (and many others) apply in some form or other in the majority of production facilities. In the case of highly automated production facilities, however, it is difficult to ascertain which causes of delay are actually relevant. This is because a malfunction on one machine can be totally irrelevant for the overall production output if, notwithstanding the malfunction, the succeeding intermediate buffer is never empty, or has already been filled up to the maximum capacity again before becoming empty.
Frequently, however, the actual effect of a delay cannot be identified merely through observation of production, since effects can only be assessed at a later point in time and at a different location in the production facility.
A more detailed analysis by digital camera recordings has already been attempted. However, since digital cameras only ever show a portion of the installation, it is scarcely possible to interrelate the multiplicity of information gathered in this way such that relationships actually become identifiable. A greater problem, however, is that camera recordings do not provide sufficient information about a possible cause of stoppage: there is a lack of knowledge about the internal states of the machines involved, and about the enabling and sensor-system signals. Moreover, the relationship to the associated production data can be established only with difficulty.
Another analysis approach is based on detailed tabular records of the cycle times and the faults that have occurred. The cycle-time tables do undoubtedly have a certain informative value when it is a matter of estimating product-related costs. For example, it can be ascertained that, on average, certain product types dwell for longer at manual reworking stations than other product types; such a finding enables certain inferences to be drawn for pricing. However, it is difficult to consider clock-cycle tables, fault tables and other tabular log records in such a joined-up manner that causalities become evident in a quantifiable form.
Overall, therefore, it must be stated that, in the case of highly automated production facilities having a high product variability, all the tools that are currently available are not adequate for rapid understanding of the functional sequence performance, in particular in the case of production facilities having several autonomous sub-regions.